Question 1

Matching

-The insolubility of nonpolar molecules in water is due to the large ______,which is the result of water molecules forming an ordered network surrounding nonpolar molecules.

Accepted Answer

A)  hydrogen bond 
B)  rotational 
C)  H3PO4 
D)  H2PO4– 
E)  HPO4 2–
F) disordered 
G) positive entropy 
H) negative entropy  
I) higher electronegativity 
J) insoluble
K) tetrahedral arrangement 
L) acid
M) base
N) only partially ionized 
A)  hydrogen bond 
B)  rotational 
C)  H3PO4 
D)  H2PO4– 
E)  HPO4 2–
F) disordered 
G) positive entropy 
H) negative entropy  
I) higher electronegativity 
J) insoluble
K) tetrahedral arrangement 
L) acid
M) base
N) only partially ionized H

Question 2

Matching

-A strong acid is completely ionized in water,whereas a weak acid is ______.

Accepted Answer

A)  hydrogen bond 
B)  rotational 
C)  H3PO4 
D)  H2PO4– 
E)  HPO4 2–
F) disordered 
G) positive entropy 
H) negative entropy  
I) higher electronegativity 
J) insoluble
K) tetrahedral arrangement 
L) acid
M) base
N) only partially ionized 
A)  hydrogen bond 
B)  rotational 
C)  H3PO4 
D)  H2PO4– 
E)  HPO4 2–
F) disordered 
G) positive entropy 
H) negative entropy  
I) higher electronegativity 
J) insoluble
K) tetrahedral arrangement 
L) acid
M) base
N) only partially ionized N

Question 3

Rank the following interactions in order of increasing strength (start with the weakest interaction).

Accepted Answer

A) ionic interactions,hydrogen bonds,London dispersion forces,covalent bonds 
B) London dispersion forces,hydrogen bonds,ionic interactions,covalent bonds 
C) London dispersion forces,ionic interactions,hydrogen bonds,covalent bonds 
D) covalent bonds,London dispersion forces,ionic interactions,hydrogen bonds 
E) hydrogen bonds,London dispersion forces,ionic interactions,covalent bonds 
A) ionic interactions,hydrogen bonds,London dispersion forces,covalent bonds 
B) London dispersion forces,hydrogen bonds,ionic interactions,covalent bonds 
C) London dispersion forces,ionic interactions,hydrogen bonds,covalent bonds 
D) covalent bonds,London dispersion forces,ionic interactions,hydrogen bonds 
E) hydrogen bonds,London dispersion forces,ionic interactions,covalent bonds B

Question 4

Biological processes can be best understood in the context of water.
a.What effect does water have on the noncovalent interactions between either charged or polar groups/molecules?
b.Why is this effect important with respect to biochemical processes?

Accepted Answer

a.Water reduces the strength of those in

Question 5

Matching

-The polarity of the O-H bond is caused by the ______ of oxygen relative to that of hydrogen.

Accepted Answer

A)  hydrogen bond 
B)  rotational 
C)  H3PO4 
D)  H2PO4– 
E)  HPO4 2–
F) disordered 
G) positive entropy 
H) negative entropy  
I) higher electronegativity 
J) insoluble
K) tetrahedral arrangement 
L) acid
M) base
N) only partially ionized 
A)  hydrogen bond 
B)  rotational 
C)  H3PO4 
D)  H2PO4– 
E)  HPO4 2–
F) disordered 
G) positive entropy 
H) negative entropy  
I) higher electronegativity 
J) insoluble
K) tetrahedral arrangement 
L) acid
M) base
N) only partially ionized

Question 6

You prepare a solution by mixing 50 mL 0.10 M sodium acetate and 150 mL 1.0 M acetic acid (pKa 4.76).
a.Calculate the pH of this solution.
b.Can this solution be used effectively as a buffer (explain your answer)?

Accepted Answer

a.50 × 10⁻³ L × 0.10 mol/L acetate = 5.0 ×

Question 7

Matching

-A phosphate buffer solution at pH = pK1 = 2.15 would have equal amounts of phosphate in the ______ form and the H2PO4- form.

Accepted Answer

A)  hydrogen bond 
B)  rotational 
C)  H3PO4 
D)  H2PO4– 
E)  HPO4 2–
F) disordered 
G) positive entropy 
H) negative entropy  
I) higher electronegativity 
J) insoluble
K) tetrahedral arrangement 
L) acid
M) base
N) only partially ionized 
A)  hydrogen bond 
B)  rotational 
C)  H3PO4 
D)  H2PO4– 
E)  HPO4 2–
F) disordered 
G) positive entropy 
H) negative entropy  
I) higher electronegativity 
J) insoluble
K) tetrahedral arrangement 
L) acid
M) base
N) only partially ionized

Question 8

In the energetics of transferring hydrocarbons from water to nonpolar solvents,the factor T$\Delta$S is commonly

Accepted Answer

A) negative. 
B) positive. 
C) unmeasurable. 
D) unimportant. 
E) assumed to be zero. 
A) negative. 
B) positive. 
C) unmeasurable. 
D) unimportant. 
E) assumed to be zero.

Question 9

Kw,the ionization constant of water,is _____ at _____.

Accepted Answer

A) 10-7;25°C 
B) 107;25K 
C) 1014;25°C 
D) 10-14;25°C 
E) 10-14;0°C 
A) 10-7;25°C 
B) 107;25K 
C) 1014;25°C 
D) 10-14;25°C 
E) 10-14;0°C

Question 10

Ice

Accepted Answer

A) is a crystal of water molecules packed in an open structure stabilized by hydrogen bonds. 
B) is less dense than liquid water. 
C) contains 17% more hydrogen bonds then water. 
D) All of the statements above are true. 
E) None of the statements above are true. 
A) is a crystal of water molecules packed in an open structure stabilized by hydrogen bonds. 
B) is less dense than liquid water. 
C) contains 17% more hydrogen bonds then water. 
D) All of the statements above are true. 
E) None of the statements above are true.

Question 11

Which of the following statements about hydrophobic interactions is not true?

Accepted Answer

A) They are caused by hydrophobic molecules interacting strongly with each other. 
B) They are the driving force for micelle formation. 
C) When nonpolar molecules come in contact with water,a highly-ordered shell of water molecules forms at the interface between the nonpolar molecules and water.A hydrophobic interaction is caused by the desire of water molecules to regain the entropy lost during this organization around the nonpolar substance by excluding the substance from interaction with water molecules. 
D) They are entropy driven. 
E) They are the main driving force for protein folding into three dimensional structures. 
A) They are caused by hydrophobic molecules interacting strongly with each other. 
B) They are the driving force for micelle formation. 
C) When nonpolar molecules come in contact with water,a highly-ordered shell of water molecules forms at the interface between the nonpolar molecules and water.A hydrophobic interaction is caused by the desire of water molecules to regain the entropy lost during this organization around the nonpolar substance by excluding the substance from interaction with water molecules. 
D) They are entropy driven. 
E) They are the main driving force for protein folding into three dimensional structures.

Question 12

The pK1 of citric acid is 3.09.What is the citric acid : monosodium citrate ratio in a 1.0 M citric acid solution with a pH of 2.09?

Accepted Answer

A) 10:1 
B) 1:1 
C) 1:10 
D) 10:11 
E) 1:11 
A) 10:1 
B) 1:1 
C) 1:10 
D) 10:11 
E) 1:11

Question 13

Osmotic pressure is a function of

Accepted Answer

A) humidity. 
B) solute size. 
C) solute concentration. 
D) van der Waals forces. 
E) solute vapor pressure. 
A) humidity. 
B) solute size. 
C) solute concentration. 
D) van der Waals forces. 
E) solute vapor pressure.

Question 14

The pH at the midpoint in the titration of an acid with a base is

Accepted Answer

A) equal to the pK of the corresponding acid. 
B) equal to the pK of the corresponding base. 
C) equal to 14 minus the pK of the corresponding acid. 
D) equal to 14 plus the pK of the corresponding base. 
E) none of the above 
A) equal to the pK of the corresponding acid. 
B) equal to the pK of the corresponding base. 
C) equal to 14 minus the pK of the corresponding acid. 
D) equal to 14 plus the pK of the corresponding base. 
E) none of the above

Question 15

Urea is a water-soluble product of nitrogen metabolism.How many hydrogen bonds can one urea molecule donate to surrounding water molecules?

Accepted Answer

A) 2 
B) 3 
C) 4 
D) 5 
E) 6 
A) 2 
B) 3 
C) 4 
D) 5 
E) 6

Question 16

Phosphoric acid is a polyprotic acid,with pK values of 2.14,6.86,and 12.38.Which ionic form predominates at pH 9.3?

Accepted Answer

A) H3PO4 
B) H2PO41− 
C) HPO42− 
D) PO43− 
E) none of the above 
A) H3PO4 
B) H2PO41− 
C) HPO42− 
D) PO43− 
E) none of the above

Question 17

Matching

-A solution containing a weak acid (pK = 7.5)and its conjugate base at pH of 8.5 has a good capacity to buffer the addition of ______.

Accepted Answer

A)  hydrogen bond 
B)  rotational 
C)  H3PO4 
D)  H2PO4– 
E)  HPO4 2–
F) disordered 
G) positive entropy 
H) negative entropy  
I) higher electronegativity 
J) insoluble
K) tetrahedral arrangement 
L) acid
M) base
N) only partially ionized 
A)  hydrogen bond 
B)  rotational 
C)  H3PO4 
D)  H2PO4– 
E)  HPO4 2–
F) disordered 
G) positive entropy 
H) negative entropy  
I) higher electronegativity 
J) insoluble
K) tetrahedral arrangement 
L) acid
M) base
N) only partially ionized

Question 18

Fatty acids such as palmitate and oleate are usually characterized as

Accepted Answer

A) hydrophobic. 
B) hydrophilic. 
C) polar. 
D) water soluble. 
E) amphiphilic. 
A) hydrophobic. 
B) hydrophilic. 
C) polar. 
D) water soluble. 
E) amphiphilic.

Question 19

A solution is made by mixing 1.0 mL of 1.0 M acetic acid (pK = 4.76,Ka = 1.74 x 10-5 )with one 999 mL of pure water.Calculate the pH of the resulting solution (assume the total volume is 1.0 L).

Accepted Answer

A) 10.1 
B) 3)0 
C) 1)0 
D) 3)9 
E) 1)32 
A) 10.1 
B) 3)0 
C) 1)0 
D) 3)9 
E) 1)32

Question 20

The pH of blood is affected by

Accepted Answer

A) the reaction of CO2 with H2O to form carbonic acid. 
B) the ionization of aqueous carbonic acid to hydronium ions and the bicarbonate anions. 
C) the decrease of the blood pH due to the production of hydronium ions. 
D) the excretion of bicarbonate and ammonium ions from the kidneys. 
E) all of the above 
A) the reaction of CO2 with H2O to form carbonic acid. 
B) the ionization of aqueous carbonic acid to hydronium ions and the bicarbonate anions. 
C) the decrease of the blood pH due to the production of hydronium ions. 
D) the excretion of bicarbonate and ammonium ions from the kidneys. 
E) all of the above

Exam 2: Water

Matching -The insolubility of nonpolar molecules in water is due to the large ______,which is the result of water molecules forming an ordered network surrounding nonpolar molecules.

Matching -A strong acid is completely ionized in water,whereas a weak acid is ______.

Rank the following interactions in order of increasing strength (start with the weakest interaction).

Biological processes can be best understood in the context of water. a.What effect does water have on the noncovalent interactions between either charged or polar groups/molecules? b.Why is this effect important with respect to biochemical processes?

Matching -The polarity of the O-H bond is caused by the ______ of oxygen relative to that of hydrogen.

You prepare a solution by mixing 50 mL 0.10 M sodium acetate and 150 mL 1.0 M acetic acid (pKa 4.76). a.Calculate the pH of this solution. b.Can this solution be used effectively as a buffer (explain your answer)?

Matching -A phosphate buffer solution at pH = pK1 = 2.15 would have equal amounts of phosphate in the ______ form and the H2PO4- form.

In the energetics of transferring hydrocarbons from water to nonpolar solvents,the factor T Δ\DeltaΔ S is commonly

Kw,the ionization constant of water,is _____ at _____.

Ice

Which of the following statements about hydrophobic interactions is not true?

The pK1 of citric acid is 3.09.What is the citric acid : monosodium citrate ratio in a 1.0 M citric acid solution with a pH of 2.09?

Osmotic pressure is a function of

The pH at the midpoint in the titration of an acid with a base is

Urea is a water-soluble product of nitrogen metabolism.How many hydrogen bonds can one urea molecule donate to surrounding water molecules?

Phosphoric acid is a polyprotic acid,with pK values of 2.14,6.86,and 12.38.Which ionic form predominates at pH 9.3?

Matching -A solution containing a weak acid (pK = 7.5)and its conjugate base at pH of 8.5 has a good capacity to buffer the addition of ______.

Fatty acids such as palmitate and oleate are usually characterized as

A solution is made by mixing 1.0 mL of 1.0 M acetic acid (pK = 4.76,Ka = 1.74 x 10-5 )with one 999 mL of pure water.Calculate the pH of the resulting solution (assume the total volume is 1.0 L).

The pH of blood is affected by

Introduction to the Chemistry of Life

Nucleotides, nucleic Acids, and Genetic Information

Amino Acids

Proteins: Primary Structure

Proteins: Three-Dimensional Structure

Protein Function Part I: Myoglobin and Hemoglobin

Carbohydrates

Lipids and Biological Membranes

Membrane Transport

Enzyme Catalysis

Enzyme Kinetics, inhibition and Control

Biochemical Signaling

Introduction to Metabolism

Glucose Catabolism

Glycogen Metabolism and Gluconeogenesis

Citric Acid Cycle

Electron Transport and Oxidative Phosphorylation

Photosynthesis

Lipid Metabolism

Amino Acid Metabolism

Mammalian Fuel Metabolism: Integration and Regulation

Nucleotide Metabolism

Nucleic Acid Structure

DNA Replication, repair and Recombination

Transcription and Rna Processing

Protein Synthesis

Regulation of Gene Expression

Filters

You prepare a solution by mixing 50 mL 0.10 M sodium acetate and 150 mL 1.0 M acetic acid (pK_a 4.76). a.Calculate the pH of this solution. b.Can this solution be used effectively as a buffer (explain your answer)?

Matching -A phosphate buffer solution at pH = pK₁ = 2.15 would have equal amounts of phosphate in the ______ form and the H₂PO₄^- form.

In the energetics of transferring hydrocarbons from water to nonpolar solvents,the factor T $\Delta$ S is commonly

K_w,the ionization constant of water,is _ at _.

The pK₁ of citric acid is 3.09.What is the citric acid : monosodium citrate ratio in a 1.0 M citric acid solution with a pH of 2.09?

A solution is made by mixing 1.0 mL of 1.0 M acetic acid (pK = 4.76,K_a = 1.74 x 10^-5 )with one 999 mL of pure water.Calculate the pH of the resulting solution (assume the total volume is 1.0 L).